1. Field of the Invention
Example embodiments of the present invention provide a dispersant for a carbon nanotube solution and a composition including the same. Other example embodiments of the present invention provide a dispersant having a hydrophobic chain structure with head groups capable of surrounding carbon nanotube particles to be adsorbed thereonto, such that dispersibility of the carbon nanotube particles produces a more concentrated carbon nanotube solution and a composition including the same.
2. Description of the Related Art
A carbon nanotube may have a nano-sized cylinder structure in which a two-dimensional graphite plate may be rolled. Electron clouds, which may be formed by π-electrons, may cover the surface of the carbon nanotube. The carbon nanotube may be a macromolecule that has various physical properties depending on the diameter, length and/or chirality thereof The carbon nanotube may have increased mechanical strength, elasticity, chemical stability and/or electric physical properties. The carbon nanotube may be applied to electron emitters, displays, secondary batteries, fuel cells, nano-sized parts and systems and high-performance complexes.
Even though the carbon nanotube may be applied to various fields, if the carbon nanotube is produced using an electric discharge process, then carbon nanotubes that have a diameter of a few nanometers and/or a length corresponding to an aspect ratio of about 1000 may be tangled. Tangled carbon nanotubes may be difficult to disperse in a solution.
A process of adding a dispersant has been used to more uniformly disperse the carbon nanotubes in the solution to avoid the above-mentioned problem. A conventional water-based dispersant may be exemplified by sodium dodecyl benzene sulfonate (NaDDBS), sodium dodecyl sulfate, and TX-100. Sodium dodecyl benzene sulfonate (NaDDBS) is the most well-known dispersant.
The conventional water-based dispersant has lower dispersibility relative to a more concentrated carbon nanotube dispersion solution; as such, it may be difficult to more uniformly disperse the carbon nanotubes at a higher concentration, and precipitation may occur due to agglomeration.